Wendy Harris, Marvin White and Wonder Dog are fictional characters from the 1973 American animated TV series Super Friends, based on the famous superheroes published by DC Comics.

Wendy and Marvin were replaced in the 1977 series The All-New Super Friends Hour with the Wonder Twins—extraterrestrial twins with the power to transform into animals and water.

Silverman and other kidvid producers had an idée fixe that the presence of a dog inevitably made a cartoon attractive to kids.[3]E.

In fact, in the cartoon, although very nice and very bright, Marvin was shown to be somewhat bumbling, often needing to learn the day's moral, such as looking up "photosynthesis" for himself rather than having Robin tell him.

When the show returned as The All-New Super Friends Hour in 1977, Wendy and Marvin had been replaced by two other teenagers, Zan and Jayna, the Wonder Twins, along with their pet, the alien monkey Gleek.

[5] Wendy, Marvin and Wonder Dog then appeared in the first nine issues of the Super Friends comic book series (November 1976 to December 1977).

The cover showed the new characters literally pushing the old trio to the side, shouting, "Your time is past, kids -- this is a job for the new Super-Friends!"

2 #186 (Dec 2002), an unnamed character identical to Wendy appears on Paradise Island as a tutor to Lyta (daughter of Circe).

[1] The pair (now fraternal twins, surname Harris) seem to be technical geniuses; Wendy mentions in their initial appearance that she and Marvin graduated from MIT on their sixteenth birthday, and in Teen Titans #40, Ravager refers to them as "tenth-level geniuses" (compared to DC characters Brainiac and Brainiac 5, both purported to be twelfth-level intellects).

This Marvin continues the tradition of his previous incarnations by wearing a shirt with a stylized "M" on the front but without the attached cape of his animated counterpart.

In reality, Wonder Dog is some sort of demonic monster in the service of a new villain called King Lycus, who appeared at the end of the issue after the beast has killed Marvin and severely mauled Wendy.

Wendy's first mission as an associate of the Oracle is to help Stephanie Brown, the new Batgirl, defeat her father the Cluemaster and save Barbara from him.

In Kingdom Come #2, an older and out-of-shape Marvin, clad in a leather jacket and other Lobo-like accoutrements, is drinking an "HB" brand of beer in a bar when Superman enters to recruit heroes for his new cause.

Wendy, Marvin, and Wonder Dog appear in the Adult Swim web series The New Adventures of the Wonder Twins episode "Be Kind, Rewind".