Adams and Cardy bring together the Teen Titans and Hawk & Dove in Teen Titans 21 (May/June 69).
The story jumps right into the plot, as it continues both from the previous issue, and also from the pages of Hawk & Dove 5, in which the quarrelling brothers follow a thief, and wind up running into the Titans. Hawk and Speedy get into conflict right away, and it doesn't help matters any that Hawk & Dove wind up aiding, and then going off with, Wonder Girl. Both teams are pursuing the Fat Man, and the aliens from Dimension X.
The villains have a teleportation device, so Hawk & Dove and Wonder Girl wind up heading to Istanbul, while Speedy, Robin and Kid Flash go to Berlin. The showier part of the story deals with Hawk & Dove, as one might expect. They are the guest stars, after all, and get a great squishing death trap to survive.
But that's not to say that the other heroes have an easy time of it, facing off against a super tank type weapon.
The aliens grow displeased with the Fat Man, who is not good enough at killing the heroes off. Hawk & Dove manage to save Speedy, which irritates the guy, but they can sense their powers fading, and costumes about to vanish. The brothers race off before this happens, though without explaining the reasons to the Titans, and rush back to the 6th and final issue of their own book.
This leaves Speedy and Wonder Girl safe and on Earth, but Robin and Kid Flash are now in the hands of the aliens, and in their dimension.
The story continues in the next issue. The appearance of Hawk & Dove must have been popular, as the brothers would return a few issues down the road and join the team.