It's Valentine's Day, and Popeye has forgotten to send Olive a valentine, so she decides to assert her independence by taking the Valentine's Day Sweetheart Cruise. There, she's convinced that she will find her "Mr. Right". However, the Sea Hag has the same idea and takes the cruise assured that she will find her "Mr. Right"; i.e., Popeye.
Popeye goes to visit Olive and finds that she has departed on the cruise. This jars his memory that he has forgotten Valentine's Day. Bluto is in hot pursuit, as he intended to ask Olive to be his valentine. The two head for the cruise ship. Bluto manages to book a passage aboard the ship, but Popeye has to talk his way on by offering to be part of the crew for free. On board, Bluto does his best to woo Olive, and Popeye tries to stop him. Meanwhile the ship is sailing into the "Devil's Triangle", home of the dreaded Sea Hag.
The Sea Hag has captured Popeye and is holding him prisoner until she can find King Neptune to marry them. However, Popeye manages to escape and go back to the cruise ship. Back on board, Popeye and Bluto compete for Olive's favors until they both spot a beautiful damsel in distress in the sea. Popeye and Bluto battle for the honor of saving her and Popeye wins, but the damsel is none other than the Sea Hag in disguise. The Sea Hag begs Popeye to stay with her and become her prince. However, Popeye's heart belongs to Olive, and he tells her so. The Sea Hag realizes that her key to winning Popeye is to get rid of Olive Oyl.
The Sea Hag casts a sleeping spell on Olive, and the only way to break it is for Popeye to pledge his love to the Sea Hag, which he refuses to do. The Sea Hag then works out a deal with Bluto to take Olive off her hands and make Popeye vow his love to her. Bluto agrees, and to make sure her plan works, Sea Hag gives him super strength. Popeye manages to outwit them both with the aid of his spinach and then tricks them into marrying each other while Popeye is reunited with his one-and-only... Olive.
- Daws Butler as J. Wellington Wimpy
- Ginny McSwain
- Allan Melvin as Bluto
- Jack Mercer as Popeye
- Barney Phillips
- Marilyn Schreffler as Olive Oyl
- Executive Producers: William Hanna and Joseph Barbera
- Producer: Alex Lovy
- Associate Producer: Neil Balnaves
- Director Oscar Dufau
- Animation Director: Chris Cuddington
- Story: Tom Dagenais, Jack Hanrahan
- Additional Dialogue: Glenn Leopold, Doug Booth
- Story Direction: George Singer, Paul Sommer
- Recording Director: Alex Lovy
- Voices: Daws Butler, Ginny McSwain, Allan Melvin, Jack Mercer, Barney Phillips, Marilyn Schreffler
- Musical Director: Hoyt Curtin
- Musical Supervisor: Paul DeKorte
- Character Design: Bob Singer, Gil DiCicco
- Layout Director: Steve Lumley
- Layout: Mike Trebert
- Animators: Sue Beak, John Burge, Martin Chatfield, Geoff Collins, Sebastian DeCosta, Dick Dunn, Peter Eastment, Don Ezard, Arthur Filloy, Peter Gardiner, Warwick Gilbert, Gerry Grabner, Greg Ingram, Pam Lofts, John Martin, Henry Neville, Laurie Sharpe, Irena Slapezynski, Mike Stapleton, Jean Tych
- Assistant Animation Supervisor: Paul Maron
- Background Supervisor: Richard Zaloudek
- Backgrounds: Jerry Liew, Zdenka Ebner, Ken Wright, Milan Zahorsky
- Graphics: Iraj Paran, Fran Burke
- Animation Checking: Narelle Nixon, Ellen Bayley, Lesley Blaney
- Xerography: Jack Pietruska
- Ink and Paint: Narelle Derrick
- Color Styling: Jenny Schowe
- Cel Painter: Peter Greenwod
- Sound Direction: Richard Olson, Bill Getty
- Camera: Mark D'Arcy-Irvine, Virginia Browne, Thomas Epperson, Carole Laird, Gary Page
- Supervising Film Editor: Larry Cowan
- Film Editor: Robert Ciaglia
- Dubbing Supervisor: Pat Foley
- Music Editors: Terry Moore, Tom Gleason
- Orchestrations: John Beal
- Additional Music by: John Beal, George Wilkins
- Effects Editors: David Stone, Mark Mangini
- Show Editor: Gil Iverson
- Negative Consultant: William E. DeBoer
- Production Manager: Doug Paterson
- Production Control: Judy McLaughlin
- Post Production Supervisor: Joed Eaton
- Animation Production: Hanna-Barbera Australia
- A Hanna-Barbera Production
- This picture has made the jurisdiction of I.A.T.S.E., affiliated with A.F.L.-C.L.O.
- Based on the comic feature "Popeye" distributed by King Features Syndicate, Inc.
- Popeye and related characters owned by King Features Syndicate, Inc. © 1978 King Features Syndicate, Inc.
- All other materials owned by Hanna-Barbera Productions, Inc. © 1978 Hanna-Barbera Productions, Inc.